Semiconductor device including a plurality of electrodes and supporters

ABSTRACT

A semiconductor device includes a plurality of electrode structures formed on a substrate; and an upper supporter group and a lower supporter between upper ends and lower ends of the plurality of electrode structures The upper supporter group includes a plurality of supporters, and at least some of the plurality of supporters each have an upper surface and a lower surface. One of the upper surface and the lower surface has a curved profile, and the other surface has a flat profile.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of Korean Patent Application No.10-2016-0065697, filed on May 27, 2016, in the Korean IntellectualProperty Office, the disclosure of which is incorporated herein in itsentirety by reference.

BACKGROUND

Example embodiments of the inventive concepts relate to a semiconductordevice. For example, at least some example embodiments relate to asemiconductor device including a capacitor.

Recently, as capacities of semiconductor devices such as dynamic randomaccess memory (DRAM) have increased and semiconductor devices have beenhighly integrated, the design rule has been continuously reduced. Inorder to operate a DRAM device, it may be desirable for a capacitanceper one cell to be greater than or equal to a threshold level. To dothis, research into a method of using a high-k material as a dielectriclayer, a method of reducing a thickness of a dielectric layer, and/or amethod of increasing a contact area between a lower electrode of acapacitor and a dielectric layer is being conducted.

SUMMARY

Example embodiments of the inventive concepts provide a semiconductordevice having improved capacitance by increasing a contact area betweena lower electrode of a capacitor and a dielectric layer.

According to an example embodiment of the inventive concepts, there isprovided a semiconductor device including: a plurality of electrodestructures on a substrate; and an upper supporter group and a lowersupporter between upper ends and lower ends of the plurality ofelectrode structures, wherein the upper supporter group includes aplurality of upper supporters, at least some of the plurality of uppersupporters each having an upper surface and a lower surface, wherein afirst one of the upper surface and the lower surface has a curvedprofile, and a second one of the upper surface and the lower surface hasa flat profile.

According to another example embodiment of the inventive concepts, thereis provided a semiconductor device including: a plurality of electrodestructures on a substrate with which a plurality of unit devices areassociated; a first supporter, a second supporter, and a third supporterseparated from one another between upper ends and lower ends of theplurality of electrode structures; a dielectric layer on the pluralityof electrode structures; and an upper electrode on the dielectric layer,wherein an upper surface of the first supporter or a lower surface ofthe second supporter have curved profiles, and a lower surface of thefirst supporter and an upper surface of the second supporter haverelatively flat profiles as compared with the upper surface of the firstsupporter or the lower surface of the second supporter.

According to another example embodiment of the inventive concepts, thereis provided a semiconductor device including: a substrate; an electrodeperpendicular to the substrate; a first supporter having a top surfaceand a bottom surface, the bottom surface of the first supporter beingsubstantially parallel to the substrate such that the bottom surface ofthe first supporter is connected substantially at right angles to theelectrode, the top surface having a different profile from the bottomsurface; and a second supporter having a top surface and a bottomsurface, the second supporter being closer to the substrate than thefirst supporter, the top surface of the second supporter beingsubstantially parallel to the substrate such that the top surface of thesecond supporter is connected substantially at right angles to theelectrode, the bottom surface having a different profile from the topsurface.

BRIEF DESCRIPTION OF THE DRAWINGS

Example embodiments of the inventive concepts will be more clearlyunderstood from the following detailed description taken in conjunctionwith the accompanying drawings in which:

FIG. 1 is a schematic plan view showing arrangements of electrodestructures and a supporter in a semiconductor device according to anexample embodiment;

FIG. 2 is a schematic perspective view showing some elements of thesemiconductor device of FIG. 1;

FIG. 3 is a cross-sectional view of a part of the semiconductor deviceof FIG. 2;

FIGS. 4 to 12 are cross-sectional view of a method of manufacturing asemiconductor device, according to an example embodiment, in aprocessing order;

FIG. 13 is a graph of cell capacitance, or Cs, gains versussemiconductor devices according to one or more example embodiments;

FIG. 14 is a cross-sectional view of a part of a semiconductor deviceaccording to an example embodiment; and

FIG. 15 is a block diagram of an electronic system including asemiconductor device according to an example embodiment.

DETAILED DESCRIPTION

Example embodiments will be described in detail with reference to theaccompanying drawings. Example embodiments, however, may be embodied invarious different forms, and should not be construed as being limitedonly to the illustrated example embodiments. Rather, these exampleembodiments are provided as examples so that this disclosure will bethorough and complete, and will fully convey the concept of the exampleembodiments to those skilled in the art. Accordingly, known processes,elements, and techniques are not described with respect to some of theexample embodiments. Unless otherwise noted, like reference numeralsdenote like elements throughout the attached drawings and writtendescription, and thus descriptions will not be repeated. In thedrawings, the sizes and relative sizes of layers and regions may beexaggerated for clarity.

FIG. 1 is a schematic plan view showing arrangements of electrodestructures and a supporter in a semiconductor device 10 according to anexample embodiment.

FIG. 2 is a schematic perspective view showing some elements of thesemiconductor device 10 of FIG. 1.

The semiconductor device 10 of FIGS. 1 and 2 may be applied to acapacitor of dynamic random access memory (DRAM), but is not limitedthereto.

Referring to FIGS. 1 and 2, the semiconductor device 10 includes asubstrate 100, a plurality of bit lines 130 and a plurality of electrodestructures 200 arranged on the substrate 100. The semiconductor device10 may further include a plurality of gate lines (not shown) disposed inthe substrate 100 or on the substrate 100.

The substrate 100 may include a rigid substrate such as a siliconsubstrate, a silicon on insulator (SOI) substrate, a gallium arsenicsubstrate, a silicon germanium substrate, a ceramic substrate, a quartzsubstrate, and a glass substrate for a display, or a flexible plasticsubstrate including polyimide, polyester, polycarbonate,polyethersulfone, polymethyl methacrylate, polyethylene naphthalate, orpolyethylene terephthalate.

Device isolation layers (not shown) may be formed on the substrate 100for separating a plurality of gate lines (not shown). The substrate 100may include unit devices (not shown) such as active devices or passivedevices of various kinds for forming semiconductor devices. The unitdevices may be, for example, DRAM cell transistors.

First to third insulating layers 124, 126, and 128 and an etch stoplayer 150 are sequentially stacked on the substrate 100. The first tothird insulating layers 124, 126, and 128 may include, for example,silicon oxide such as borosilicate glass (BSG), phosphosilicate glass(PSG), borophosphosilicate glass (BPSG), undoped silicate glass (USG),tetraethlyorthosilicate glass (TEOS), and/or high densityplasma-chemical vapour deposition (HDP-CVD). The etch stop layer 150 mayinclude SiON or SiN. In some example embodiments, the etch stop layer150 may be omitted.

Each of the plurality of bit lines 130 may extend in a direction that isperpendicular to a direction, in which the gate lines (not shown)extend, e.g., a y-axis direction, in the second insulating layer 126. Insome example embodiments, the bit line 130 may be arranged in thesubstrate 100 as an embedded bit line. The bit line 130 may beelectrically connected to the substrate 100 via a direct contact plug135 that penetrates through the first and second insulating layers 124and 126. The bit line 130 and the direct contact plug 135 mayrespectively include a conductive material, e.g., tungsten (W), titanium(Ti), aluminum (Al), copper (Cu), tantalum (Ta), tungsten nitride (WNx),titanium nitride (TiNx), aluminum nitride (AlNx), tantalum nitride(TaNx), and titanium-aluminum nitride (TiAlxNy). Otherwise, the bit line130 and the direct contact plug 135 may include doped polysilicon.

The plurality of electrode structures 200 may be repeatedly arranged onthe substrate 100 along an x-axis direction and the y-axis direction, asshown in FIG. 1. As shown in FIG. 1, the plurality of electrodestructures 200 may be separated from one another in the x-axis directionat an interval of a first pitch D1, and may be separated from oneanother in the y-axis direction at an interval of a second pitch D2. InFIG. 1, the first pitch D1 is shown to be nearly equal to the secondpitch D2, but is not limited thereto.

The electrode structures 200 may be arranged as a honeycomb-likestructure, in which the electrode structures 200 in adjacent columns orrows cross each other. When the electrode structures 200 cross eachother, distances between adjacent electrode structures 200 may beconstant.

The electrode structures 200 may have thin and long shapes that extendin a direction that is perpendicular to the x and y-axis directions,e.g., z-axis direction, on the substrate 100. The electrode structures200 may have an aspect ratio, that is, a ratio of a height with respectto a width, of about 10 to about 35, but are not limited thereto.

In an example embodiment, the electrode structures 200 are shown aspillars, but in some other example embodiments, the electrode structures200 may have hollow cylindrical shapes. A ‘pillar type’ may denote acylinder with a filled inside, as shown in FIG. 2, and a ‘hollowcylindrical type’ may denote a cylinder with an empty inside. Theelectrode structures 200 may include, for example, at least one of dopedpolysilicon, TiN, W, Ti, Ru, and WN. The electrode structures 200 mayinclude an oxide-based conductive material such as ruthenium oxide(RuOx). The electrode structures 200 may be formed by a sputteringprocess, a physical vapour deposition (PVD) process, and an atomic layerdeposition (ALD) method, but example embodiments of the inventiveconcepts are not limited thereto.

Each of the electrode structures 200 may be connected to a source/drainregion (not shown) in the substrate 100 via a capacitor contact plug 140in a certain region. In an example embodiment, the electrode structure200 is directly connected to the substrate 100 via the capacitor contactplug 140, but example embodiments of the inventive concepts are notlimited thereto. The electrode structure 200 may be connected to thesubstrate 100 via, for example, at least one contact pad (not shown)and/or at least one contact plug (not shown).

The number of electrode structures 200 may be greater or less than thatof electrode structures 200 shown in FIG. 1. In an example embodiment,the electrode structure 200 may correspond to a lower electrode of thecapacitor. However, one or more example embodiments are not only appliedto the lower electrode of the cell capacitor in DRAM, but may be alsoapplied to structures having high aspect ratios and arranged repeatedly.

A first supporter 160, a second supporter 170, and a third supporter 180may be located between uppermost and lowermost ends of the plurality ofelectrode structures 200. The first to third supporters 160, 170, and180 may prevent inclination of the electrode structures 200 having alarge aspect ratio. The first and second supporters 160 and 170 may forman upper supporter group, and the third supporter 180 may form a lowersupporter. The first to third supporters 160, 170, and 180 may supportthe electrode structures 200 by partially supporting side surfaces ofthe electrode structures 200. The first to third supporters 160, 170,and 180 may include plates that are arranged in parallel with an uppersurface of the substrate 100 at certain heights on the electrodestructures 200.

The first to third supporters 160, 170, and 180 may respectively includefirst to third openings 160 a, 170 a, and 180 a. The first to thirdopenings 160 a, 170 a, and 180 a may be repeatedly and regularly formedin the first to third supporters 160, 170, and 180. In some exampleembodiments, the first to third openings 160 a, 170 a, and 180 a may bedifferent from one another in locations, sizes, or shapes thereof. Thefirst to third openings 160 a, 170 a, and 180 a may have a shape, alength of which in the x-axis direction is three times greater than thefirst pitch D1 and a length of which in the y-axis direction is equal tothe second pitch D2, but example embodiments are not limited thereto.That is, the first to third openings 160 a, 170 a, and 180 a may beformed as a parallelogram, a trapezoid, a triangle, or a circle.

Post-processes on portions under the first to third supporters 160, 170,and 180 may be performed via the first to third openings 160 a, 170 a,and 180 a. As an example of such post-processes, a first, second, andthird mold layers 152, 154, and 156 (see FIG. 4), formed respectivelyunder the first to third supporters 160, 170, and 180 may be removedand/or a dielectric layer 202 (see FIG. 12) and an upper electrode 204(see FIG. 12) may be formed on surfaces of the electrode structures 200when the electrode structure 200 is the lower electrode of the cellcapacitor in the DRAM.

As shown in FIG. 2, the first to third supporters 160, 170, and 180 maybe disposed at certain heights of the electrode structure 200. Forexample, the first and second supporters 160 and 170 may be separatedfrom opposite ends of the electrode structure 200 in the z-axisdirection and located along the center of the electrode structure 200 inthe z-axis direction. The first and second supporters 160 and 170 may beseparated from each other in the z-axis direction. In some exampleembodiments, the first supporter 160 may be formed slightly under anupper end portion of the electrode structure 200.

In addition, the third supporter 180 may be located at a lower end, thatis, lower than an intermediate portion of the electrode structure 200.As such, the electrode structure 200 may have a side surface that isexposed by a fourth height L4 under the third supporter 180, and a sidesurface that is exposed by a third height L3 between the third supporter180 and the second supporter 170. The fourth height L4 may be equal toor greater than the third height L3. In addition, the electrodestructure 200 may have a side surface that is exposed by a second heightL2 between the second supporter 170 and the first supporter 160, and aside surface that is exposed to a first height L1 above the firstsupporter 160. The first height L1 may be less than the second heightL2, and the second height L2 may be less than the third height L3.

In some example embodiments, an upper surface of the first supporter 160and an upper surface of the electrode structures 200 may be at the samelevel so that the electrode structures 200 may not protrude upward. Inaddition, the number of supporters is not limited to the above example,and four or more supporters may be arranged.

The first and second supporters 160 and 170 may include the samematerial as each other. A thickness T1 of the first supporter 160 and athickness T2 of the second supporter 170 may be equal to or differentfrom each other. In some other embodiments, the first supporter 160 andthe second supporter 170 both may have multi-layered structures.

The first and second supporters 160 and 170 may include a material thathas etch selectivity with respect to the first, second, and third moldlayers 152, 154, and 156 (see FIG. 4) for forming the electrodestructures 200. In some example embodiments, a limulus amoebocyte lysate(LAL) lift-off process is used in a post-process for removing the first,second, and third mold layers 152, 154, and 156, a material having a lowetch rate with respect to the LAL and having dielectric characteristicsmay be used. For example, the first and second supporters 160 and 170may include one of SiN, SiCN, TaO, and TiO₂, but are not limitedthereto.

In one example embodiment, the first and second supporters 160 and 170may include SiCN, or silicon carbon nitride. In silicon carbon nitride,a carbon rate may range from 0.1 atom % to 15 atom %. If the first andsecond supporters 160 and 170 include carbon, warpage of the first andsecond supporters 160 and 170 may be reduced.

A thickness T3 of the third supporter 180 may be less than those T1 andT2 of the first and second supporters 160 and 170. In some exampleembodiments, the third supporter 180 may have a multi-layered structure.The third supporter 180 may include a material having etch selectivitywith respect to the first, second, and third mold layers 152, 154, and156 (see FIG. 4) for forming the electrode structures 200. In someexample embodiments, in a case where the LAL lift-off process is used ina post-process for removing the first, second, and third mold layers152, 154, and 156, a material having a low etch rate with respect to theLAL and having dielectric characteristics may be used. For example, thethird supporter 180 may include one of SiN, SiCN, TaO, and TiO₂, but isnot limited thereto.

In one example embodiment, the third supporter 180 may include SiCN, orsilicon carbon nitride. In silicon carbon nitride, a carbon rate mayrange from 0.1 atom % to 15 atom %. If the third supporter 180 includescarbon, warpage of the third supporter 180 may be reduced.

FIG. 3 is a cross-sectional view showing an enlarged view of region A inFIG. 2.

Referring to FIG. 3, an upper surface of the first supporter 160 and alower surface of the second supporter 170 may respectively have aprofile that varies depending on a distance to the electrode structure200. Due to the variation in the profile, the thickness of the firstsupporter 160 and the second supporter 170 may be reduced towards theelectrode structures 200.

A first damaged portion 173 may be formed in the upper surface of thefirst supporter 160, and a second damaged portion 174 may be formed inthe lower surface of the second supporter 170. The first damaged portion173 may be generated due to dry etching and/or wet etching during theprocesses, and the second damaged portion 174 may be generated due tothe wet etching during the processes.

Unlike the upper surface of the first supporter 160 and the lowersurface of the second supporter 170 respectively having the first andsecond damaged portions 173 and 174, a lower surface of the firstsupporter 160 and an upper surface of the second supporter 170 may haverelatively flat profiles. That is, during the manufacturing processes ofthe semiconductor device according to the example embodiments, the thirdmold layer 156 (see FIG. 4) formed between the first supporter 160 andthe second supporter 170 may protect the lower surface of the firstsupporter 160 and the upper surface of the second supporter 170 againstdamage caused by the etching process so that the lower surface of thefirst supporter 160 and the upper surface of the second supporter 170may have flat profiles. Accordingly, a contact area between thesupporters and the electrode structures 200 increases when beingcompared with the shape caused by the etching damage, margins withrespect to isolation of the supporters or cracks may be improved. Inaddition, in one example embodiment, when the first and secondsupporters 160 and 170 include SiCN and the third mold layer 156 (seeFIG. 4) includes SiN, the third mold layer 156 prevents a bowing effect,or curvature, from being generated in the side surface portion of theelectrode structure 200 exposed between the first and second supporters160 and 170 during a post wet-etching process, and accordingly, the sidesurface portion of the electrode structure 200 may have a constantprofile.

FIGS. 4 to 12 are cross-sectional views of a method of manufacturing asemiconductor device, according to an example embodiment. FIGS. 4 to 12respectively show cross-sectional structures corresponding to across-section taken along a line II-II' of FIG. 1.

Referring to FIG. 4, a substrate 100, on which a plurality of bit lines130, a plurality of capacitor contact plugs 140, and a plurality of gatelines (not shown) are formed, is provided.

Device isolation layers (not shown) for separating the plurality of gatelines (not shown) may be formed on the substrate 100. The substrate 100may include unit devices (not shown) that are necessary for forming asemiconductor device such as active devices or passive devices ofvarious kinds. The unit devices may be, for example, dynamic randomaccess memory (DRAM) cell transistors.

The first to third insulating layers 124, 126, and 128 and the etch stoplayer 150 may be sequentially stacked on the upper surface of thesubstrate 100. The first to third insulating layers 124, 126, and 128may include, for example, silicon oxide such as borosilicate glass(BSG), PhosphoSilicate glass (PSG), BoroPhosphoSilicate Glass (BPSG),Undoped Silicate Glass (USG), TetraEthlyOrthoSilicate Glass (TEOS), orHigh Density Plasma-CVD (HDP-CVD). In some example embodiments, the etchstop layer 150 may be omitted.

The bit lines 130 may extend in a direction that is perpendicular to adirection, in which the gate lines (not shown) extend, for example, in ay-axis direction, in the second insulating layer 126. In some exampleembodiments, the bit lines 130 may be arranged in the substrate 100 asembedded bit lines. The bit lines 130 may be electrically connected tothe substrate 100 via direct contact plugs 135 that penetrate throughthe first and second insulating layers 124 and 126. The bit lines 130and the direct contact plugs 135 may respectively include a conductivematerial, for example, W, Ti, Al, Cu, Ta, tungsten nitride (WNx),titanium nitride (TiNx), aluminum nitride (AlNx), tantalum nitride(TaNx), and titanium-aluminum nitride (TiAlxNy). Otherwise, the bitlines 130 may include doped polysilicon.

A stack structure, in which the first mold layer 152, the thirdsupporter 180, the second mold layer 154, the second supporter 170, thethird mold layer 156, the first supporter 160, and the hard mask layer158 are sequentially stacked, is formed on the etch stop layer 150. Afirst mask pattern 190 for forming the electrode structures 200 (seeFIG. 2) may be formed on the stack structure.

The first to third supporters 160, 170, and 180 may include SiCN. In acase where the first to third supporters 160, 170, and 180 include acarbon-based material layer, warpage characteristics of the first tothird supporters 160, 170, and 180 may be reduced. In order to preventloss caused by plasma damage, the carbon-based material layer mayinclude carbon at an appropriate rate. For example, the carbon-basedmaterial layer may include carbon of 0.1 atom % to 15 atom %.

A processing condition for forming the first to third supporters 160,170, and 180 may range from 250° C. to 550° C., and may use a mixturegas of SiH₄ and NH₃. In addition, N₂ may be used or N₂ and He may beused together as a carrier gas.

The first mold layer 152 and the second mold layer 154 may include amaterial having etch selectivity with respect to the second supporter170 and the third supporter 180. In some example embodiments, when a LALlift-off process is performed, the first mold layer 152 and the secondmold layer 154 may respectively include an oxide layer having a highetch rate with respect to the LAL, but example embodiments are notlimited thereto.

The third mold layer 156 may include a material having etch selectivitywith respect to the first supporter 160 and the second supporter 170. Inaddition, the third mold layer 156 may include a material that also hasetch selectivity with respect to the first mold layer 152 and the secondmold layer 154. In some example embodiments, in a case where the LALlift-off process is performed, the third mold layer 156 may have an etchrate with respect to the LAL, wherein the etch rate is higher than thoseof the first and second supporters 160 and 170 but is lower than thoseof the first and second mold layers 152 and 154. The third mold layer156 may protect the lower surface of the first supporter 160 and theupper surface of the second supporter 170 against the damage caused dueto the dry etching and/or the wet etching. That is, after the dryetching and/or wet etching process, the lower surface of the firstsupporter 160 and the upper surface of the second supporter 170 may haveflat profiles, and have an increased contact area to the electrodestructures 200 as compared with the shape caused by the etching damage.Thus, margins with respect to the isolation of the supporters or cracksmay be increased.

The third mold layer 156 may include SiN, SiON, or SiN or SiON dopedwith C, B, or P, but example embodiments of the inventive concepts arenot limited thereto. As an example, when the first and second supporters160 and 170 may include SiCN and the third mold layer 156 includes SiN,the third mold layer 156 may prevent a bowing effect from generating inthe side surface portion of the electrode structure 200 exposed betweenthe first and second supporters 160 and 170 during the post wet-etchingprocess, so that the electrode structure 200 may have an even profile.

Referring to FIG. 5, on portions where the electrode structures 200 areto be formed, the hard mask layer 158, the first supporter 160, thethird mold layer 156, the second supporter 170, the second mold layer154, the third supporter 180, and the first mold layer 152 are etched byusing the first mask pattern 190 (see FIG. 4) as an etching mask to forma plurality of first holes H1 penetrating the above layers. In the aboveetching process, the etch stop layer 150 may be used to stop theetching. After forming the first holes H1, the etch stop layer 150exposed on bottom surfaces of the first holes H1 is also removed toexpose the capacitor contact plugs 140.

Referring to FIG. 6, a conductive material is embedded in the firstholes H1 to form the electrode structures 200. The conductive materialmay include, for example, at least one of doped polysilicon, silicongermanium (SiGe), TiN, W, Ti, Ru, and WN. In some example embodiments,the electrode structure 200 may include an oxide-based conductivematerial such as ruthenium oxide (RuO_(x)).

Referring to FIG. 7, a second mask pattern 192 for forming an opening OPmay be formed on the electrode structures 200 and the hard mask layer158. The hard mask layer 158 is patterned by using the second maskpattern 192. For example, when the hard mask layer 158 includes asilicon oxide layer, the hard mask layer 158 may be patterned by awet-etching or dry-etching process using an etchant that may selectivelyremove the silicon oxide layer.

Referring to FIG. 8, the first supporter 160, the third mold layer 156,and the second supporter 170 that are exposed are removed to form theopening OP. The first supporter 160, the third mold layer 156, and thesecond supporter 170 that are exposed may be removed between theelectrode structures 200 in the opening OP, as shown in FIG. 1.

In this process, the removing process may be performed without using anadditional mask pattern. For example, in a case where the firstsupporter 160 includes a silicon nitride layer, the first supporter 160may be patterned by a wet-etching or a dry-etching process using anetchant that may selectively remove the silicon nitride layer, and then,a first opening 160 a may be formed. In this case, in the other portionthan the first opening 160 a, an upper portion of the hard mask layer158 is partially removed, and the first supporter 160, the third moldlayer 156, and the second supporter 170 are removed through the firstopening 160 a to form the opening OP. Therefore, when the hard masklayer 158 is formed as described above with reference to FIG. 7, athickness of the hard mask layer 158 may be determined taking intoaccount the present process. That is, the thickness of the hard masklayer 158 may be determined so that the first supporter 160 except thefirst opening 160 a may not be removed until all of the first supporter160, the third mold layer 156, and the second supporter 170 in theopening OP are removed. If the hard mask layer 158 remains, the hardmask layer 158 may be removed through an additional process.

The first opening 160 a may be repeatedly and regularly formed in thefirst supporter 160, and a second opening 170 a may also be repeatedlyand regularly formed in the second supporter 170. For example, the firstand second openings 160 a and 170 a may be formed as rectangles, but arenot limited thereto, that is, the first and second openings 160 a and170 a may be formed as parallelograms, trapezoid, triangles, or circles.

Through the process of removing the first supporter 160, the third moldlayer 156, and the second supporter 170, the second mold layer 154 ispartially exposed through the opening OP. Post-processes may beperformed on portions under the first or second supporter 160 or 170through the opening OP.

Referring to FIG. 9, the remaining portion of the hard mask layer 158(see FIG. 8), a part of the third mold layer 156, and the second moldlayer 154 may be removed. For example, when the hard mask layer 158includes a silicon oxide layer, the hard mask layer 158 may be removedthrough a wet-etching or a dry-etching process using an etchant that mayselectively remove the silicon oxide layer. After or simultaneously withthe removing of the hard mask layer 158, a part of the third mold layer156 and the second mold layer 154 may be removed by providing theetchant through the opening OP. If the second mold layer 154 includes asilicon oxide layer, the second mold layer 154 and a part of the thirdmold layer 156 may be removed through the wet-etching or dry-etchingprocess using an etchant that may selectively remove the silicon oxidelayer. According to the embodiment, the hard mask layer 158 and thesecond mold layer 154 may include an oxide layer (e.g., silicon oxidelayer), and the third mold layer 156 may include the silicon nitridelayer. In some example embodiments, the third mold layer 156 may includea bowing block SiN (B-SiN) or a bowing block SiON (B-SiON), which may bedoped with C, B, or P. Therefore, the LAL lift-off process using a LALsolution including ammonium fluoride (NH₄F), hydrofluoric acid (HF), andwater may be performed to remove the hard mask layer 158, a part of thethird mold layer 156, and the second mold layer 154 together.

According to the LAL lift-off process, an upper space for separating thefirst supporter 160 from the second supporter 170 and an intermediatespace for separating the second supporter 170 from the third supporter180 may be generated. The electrode structures 200 are supported by thefirst and second supporters 160 and 170, and side walls of the electrodestructures 200 may be partially exposed through the opening OP.

Referring to FIG. 10, the third supporter 180 is patterned to form athird opening 180 a. For example, an etchant is provided through theopening OP so that the third supporter 180 that is exposed through theopening OP may be partially removed by the wet-etching or dry-etching toform a third opening 180 a pattern in the third supporter 180. Accordingto an example embodiment, shapes of the first and second openings 160 aand 170 a may be transferred to the third supporter 180 withoutperforming additional photo processes so as to form the third supporter180. Accordingly, the third opening 180 a may be formed in the thirdsupporter 180, in a shape similar to or the same as those of the firstand second openings 160 a and 170 a. The third opening 180 a in thethird supporter 180 may partially expose the first mold layer 152, andpartially expose the side walls of the electrode structures 200.

When the third opening 180 a of the third supporter 180 is formed, theetchant attacks the first supporter 160, and accordingly, a part of thefirst supporter 160, e.g., an upper portion of the first supporter 160,may be lost and may be reduced in thickness thereof. A loss amount ofthe first supporter 160 may vary depending on an etching rate of thefirst supporter 160. Therefore, a thickness of the first supporter 160may be appropriately set, taking into account the loss amount of thefirst supporter 160 while the third supporter 180 is patterned by, forexample, an etch-back process. Since the upper portion of the firstsupporter 160 is partially lost, upper end portions of the electrodestructures 200 may protrude more than the upper surface of the firstsupporter 160.

Referring to FIG. 11, an etchant may be provided through the thirdopening 180 a of the third supporter 180 so as to remove the third moldlayer 156 (see FIG. 10) and the first mold layer 152 (see FIG. 10) thatare remained. For example, if the first mold layer 152 includes asilicon oxide layer, the first mold layer 152 may be removed by thewet-etching or dry-etching process using an etchant that may selectivelyremove the silicon oxide layer. The first mold layer 152 may include,for example, an oxide layer (e.g., silicon oxide layer). Therefore, theLAL lift-off process using a LAL solution including NH₄F, HF, and watermay be performed to remove the third mold layer 156 that remains (seeFIG. 10), and the first mold layer 152 (see FIG. 10) together.

According to the LAL lift-off process, a lower space for separating thethird supporter 180 from the etch stop layer 150 may be generated.According to the embodiment, through two LAL lift-off processes, thelower space between the third supporter 180 and the etch stop layer 150,the intermediate space between the second supporter 170 and the thirdsupporter 180, and the upper space between the first supporter 160 andthe second supporter 170 may be generated.

The first to third supporters 160, 170, and 180 of mesh types areseparate from one another by the upper space and the intermediate space,and may configure a triple-structured supporter that supports upper andlower sides of the electrode structure 200 while partially surroundingthe side wall of the electrode structure 200 that extends in a Z-axisdirection. The first to third supporters 160, 170, and 180 may bearranged up and down in the Z-axis direction, in which the electrodestructure 200 extends. The first supporter 160 may include Y patternsextending in a Y-axis direction and X patterns extending in an X-axisdirection. The X-axis direction may be perpendicular to the Y-axisdirection. The Y patterns contact the electrode structures 200 tosupport the electrode structures 200, and the X patterns support theelectrode structures 200, and at the same time, connect the Y patternsto one another. Accordingly, robustness of the first supporter 160 andproperty for supporting the electrode structures 200 may be ensured.This will be applied to the second and third supporters 170 and 180, aswell.

In the present specification, the triple-structured supporter is mainlydescribed, but one or more example embodiments are not limited thereto,that is, other example embodiments relate to a supporter having aquadruple or greater structure.

Referring to FIG. 12, a dielectric layer 202 and an upper electrode 204may be formed along surfaces of the electrode structures 200. Thedielectric layer 202 and the upper electrode 204 may be formed alongexposed surfaces of the first to third supporters 160, 170, and 180 andexposed surfaces of the electrode structures 200. According to the aboveseries of processes, a capacitor having the electrode structures 200 andthe upper electrode 204, which face each other as the dielectric layer202 is interposed therebetween, is formed on the substrate 100, and asemiconductor device such as DRAM including a triple supporter forsupporting the electrode structures 200 may be implemented. Thedielectric layer 202 may be formed by stacking a metal oxide layer on ametal nitride layer by a chemical vapour deposition (CVD) method or anatomic layer deposition (ALD) method. The dielectric layer 202 is notlimited to a dual-layered structure, but may have a triple or morelayered structure. The metal nitride layer may include an aluminumnitride (AlN) layer, a boron nitride (BN) layer, a zirconium nitride(Zr₃N₄) layer, or a hafnium nitride (Hf₃N₄) layer, but is not limitedthereto. The metal oxide layer may be a single layer selected from thegroup consisting of a ZrO₂ layer, an HfO₂ layer, and a Ta₂O₃ layer, or acombination thereof, but example embodiments are not limited thereto.

For example, the upper electrode 204 is formed on the dielectric layer202. The upper electrode 204 may include, for example, TIN, TiAlN, TAN,W, WN, Ru, RuO₂, SrRuO₃, Ir, IrO₂, platinum, or a combination thereof,but example embodiments are not limited thereto. The upper electrode 204may be formed by the CVD method.

According to an example embodiment, the triple supporters may supportthe electrode structures 200 from upper and lower portions, andaccordingly, even when the electrode structures 200 are formed as largeas possible in vertical heights, leaning of the electrode structures 200may be prevented or restrained. In addition, the electrode structures200 are exposed between the first supporter 160 and the second supporter170 to be used as a capacitor, and a cell capacitance, or Cs gain may beensured as much as possible.

Referring to FIG. 13, a graph shows a Cs gain versus a thickness of thethird mold layer 156 according to the embodiment.

In the graph of FIG. 13, x axis denotes semiconductor devices having thethird mold layer 156 of different thicknesses, wherein the third moldlayer 156 includes SiN, with respect to the semiconductor device (REF)having no third mold layer 156, as variables. In addition, y axisdenotes Cs gains with respect to the semiconductor devices. Here, thethickness of the third mold layer 156 and the Cs gain increase in arrowdirections of the x axis and the y axis. That is, the thickness of thethird mold layer 156 may be arranged in an order of Inv_1<Inv_2<Inv_3.

Through the above graph, as the thickness of the third mold layer 156increases, that is, a distance between the first supporter 160 and thesecond supporter 170 increases, exposed portions of the electrodestructures 200 increase and an area of the lower electrode in thecapacitor increases, and accordingly, the Cs gain increases. That is,according to example embodiments, the semiconductor device may beimplemented while reducing a propensity or preventing collapse of theelectrode structures 200 and adjusting an optical thickness of the thirdmold layer 156 for ensuring maximum Cs gain.

FIG. 14 is a cross-sectional view of a semiconductor device, in whicharrangements of electrode structures 300 and supporters areschematically shown, according to an example embodiment.

In FIG. 14, like reference numerals as FIG. 12 denote the same elements.Referring to FIG. 14, each of a plurality of electrode structures 300 ofthe embodiment may be formed as a hollow cylindrical type. When theelectrode structure 300 is formed as a hollow cylindrical typecapacitor, an upper surface, an external surface, and an internalsurface of the electrode structure 300 may be all used as capacitorregions, and accordingly, an amount of a conductive material for formingthe electrode structure 300 may be reduced. The electrode structure 300may include, for example, at least one of TiN, W, Ti, Ru, and WN. Insome example embodiments, the electrode structure 300 may include anoxide-based conductive material such as RuOx. The electrode structure300 may be formed by a metal organic CVD method.

The electrode structure 300 may be connected to source/drain regions(not shown) in the substrate 100 via a capacitor contact plug 140 in apredetermined region. In the embodiment, the electrode structure 300 isshown to be directly connected to the substrate 100 via the capacitorcontact plug 140, but is not limited thereto. For example, the electrodestructure 300 may be connected to the substrate 100 via at least onecontact pad (not shown) and/or at least one contact plug (not shown).

The first supporter 160, the second supporter 170, and the thirdsupporter 180 may be located between upper and lower ends of theplurality of electrode structures 300. The first to third supporters160, 170, and 180 may prevent the electrode structures 300, each havinga large aspect ratio, from leaning. The first and second supporters 160and 170 may form an upper supporter group, and the third supporter 180may form a lower supporter. The first to third supporters 160, 170, and180 support the electrode structures 300 by partially contacting sidesurfaces of the electrode structures 300. The first to third supporters160, 170, and 180 may each have a plate-type shape disposed in parallelwith an upper surface of the substrate 100 at a predetermined height ofthe electrode structures 300.

As shown in FIG. 14, the first to third supporters 160, 170, and 180 maybe respectively disposed at desired, or alternatively predeterminedheights of the electrode structures 300. For example, the first andsecond supporters 160 and 170 may be located higher than a center of theelectrode structures 300 in a perpendicular direction, separating fromopposite ends of the electrode structures 300 in the z-axis direction.In addition, the third supporter 180 may be located at a lower endportion, that is, lower than the center of the electrode structures 300.The first and second supporters 160 and 170 may be spaced from eachother in a perpendicular direction. In some example embodiments, thefirst supporter 160 may be located slightly lower than an upper endportion of the electrode structures 300.

In another example embodiment, the first supporter 160 may be disposedso that an upper surface of the first supporter 160 and the uppersurfaces of the electrode structures 300 are at the same level, andthus, the electrode structures 300 may not protrude upward. In addition,the number of supporters is not limited to the above example, but fouror more supporters may be arranged.

The first and second supporters 160 and 170 may include the samematerial as each other. The thickness T1 of the first supporter 160 andthe thickness T2 of the second supporter 170 may be equal to ordifferent from each other. In another example embodiment, the first andsecond supporters 160 and 170 may have multi-layered structures.

The first and second supporters 160 and 170 may include a materialhaving etch selectivity with respect to a mold layer (not shown) forforming the electrode structures 300. In some example embodiments, whenthe LAL lift-off process is used in a post-process for removing the moldlayer (not shown), a material having a lower etch rate with respect tothe LAL and having dielectric characteristics may be used to form thefirst and second supporters 160 and 170. For example, the first andsecond supporters 160 and 170 may include one of SiN, SiCN, TaO, andTiO₂, but are not limited thereto.

In one example embodiment, the first and second supporters 160 and 170may include SiCN. In SiCN, a carbon rate may range from 0.1 atom % to 15atom %. When the first and second supporters 160 and 170 include carbon,warpage of the first and second supporters 160 and 170 may be reduced.

The thickness T3 of the third supporter 180 may be less than those T1and T2 of the first and second supporters 160 and 170. In anotherexample embodiment, the third supporter 180 may include a multi-layeredstructure. The third supporter 180 may include a material having etchselectivity with respect to a mold layer (not shown) for forming theelectrode structures 300. In some example embodiments, when the LALlift-off process is used in a post-process for removing the mold layer(not shown), a material having a lower etch rate with respect to the LALand having dielectric characteristics may be used to form the thirdsupporter 180. For example, the third supporter 180 may include one ofSiN, SiCN, TaO, and TiO₂, but is not limited thereto.

In one example embodiment, the third supporter 180 may include SiCN. InSiCN, a carbon rate may range from 0.1 atom % to 15 atom %. When thethird supporter 180 includes carbon, warpage of the third supporter 180may be reduced.

Referring to FIG. 14, an upper surface of the first supporter 160 and alower surface of the second supporter 170 may have profiles that varydepending on distances to the electrode structures 300. Due to thevariation in the profiles, the thickness of the first and secondsupporters 160 and 170 may be reduced towards the electrode structures300.

The upper surface of the first supporter 160 may be damaged by thedry-etching and/or the wet-etching, and the lower surface of the secondsupporter 170 may be damaged due to the wet-etching. Unlike the uppersurface of the first supporter 160 and the lower surface of the secondsupporter 170 having the damages, the lower surface of the firstsupporter 160 and the upper surface of the second supporter 170 may haveflat profiles. That is, during the manufacturing processes of thesemiconductor device according to the one or more embodiments, a moldlayer (not shown) may be formed between the first supporter 160 and thesecond supporter 170 so as to protect the lower surface of the firstsupporter 160 and the upper surface of the second supporter 170 againstdamage caused by the etching processes and to form the flat profiles.Accordingly, a contact area may be increased comparing with the shapesobtained due to the etching damage, and thus, margins with respect tothe isolation of the supporter or the crack may be improved. Inaddition, in one example embodiment, when the first and secondsupporters 160 and 170 include SiCN and the first and second supporters160 and 170 are formed by removing the mold layer (not shown)therebetween through the wet-etching process, a bowing effect may beprevented from occurring on the side surfaces of the electrodestructures 300, which are exposed between the first and secondsupporters 160 and 170, during a post wet etching process, so that theexposed side surfaces of the electrode structures 300 may have uniformprofiles.

FIG. 15 is a diagram of a system 1000 including a semiconductor devicemanufactured according to an example embodiment.

In detail, the system 1000 according to an example embodiment mayinclude a controller 1010, an input/output device (I/O) 1020, a memorydevice 1030, an interface 1040, and a bus 1050. The controller 1010, theI/O 1020, the memory device 1030, and/or the interface 1040 may beconnected to one another via the bus 1050. The bus 1050 corresponds to apath through which data is transferred. The system 1000 may be a mobilesystem or a system sending/receiving information. In some exampleembodiments, the mobile system may be applied to a personal digitalassistant (PDA), a portable computer, a web tablet, a wireless phone, amobile phone, a digital music player, a memory card, or all kinds ofelectronic appliances capable of wirelessly transmitting and/orreceiving information.

The controller 1010 controls execution programs in the system 1000, andmay include a microprocessor, a digital signal processor, amicrocontroller, or similar devices. The I/O 1020 may input or outputdata to/from the system 1000. The system 1000 may be connected to anexternal device, e.g., a personal computer or a network, via the I/O1020, and may exchange data with the external device. The I/O 1020 mayinclude, for example, a keypad, a keyboard, or a display.

The memory device 1030 stores codes and/or data for operating thecontroller 1010, or data processed by the controller 1010. The memorydevice 1030 may include the semiconductor device according to one ormore embodiments. For example, the memory device 1030 may include atleast one of the semiconductor devices manufactured by theabove-described methods. Therefore, the memory device 1030 may have aplurality of cells with a higher Cs.

The interface 1040 may be a data transmission path between the system1000 and an external device. The controller 1010, the I/O 1020, thememory device 1030, and the interface 1040 may communicate with oneanother via the bus 1050.

The system 1000 according to example embodiments may be used, forexample, in a mobile phone, an MP3 player, a navigation system, aportable multimedia player (PMP), a solid state disk (SSD), and/orhousehold appliances. However, example embodiments are not limitedthereto.

While some of the inventive concepts have been particularly shown anddescribed with reference to embodiments thereof, it will be understoodthat various changes in form and details may be made therein withoutdeparting from the spirit and scope of the following claims.

What is claimed is:
 1. A semiconductor device comprising: a plurality ofelectrode structures on a substrate, the plurality of electrodestructures having side surfaces; and an upper supporter group and alower supporter between upper ends and lower ends of the plurality ofelectrode structures, respectively, the upper supporter group includinga plurality of upper supporters, at least some of the plurality of uppersupporters each having an upper surface and a lower surface, the atleast some of the plurality of upper supporters having a thicknessbetween the upper surface and the lower surface, respectively, wherein afirst one of the upper surface and the lower surface has a curvedprofile, and a second one of the upper surface and lower surface has aflat profile, and at least some of the plurality of upper supportershave the thickness that decreases towards the plurality of electrodestructures.
 2. The semiconductor device of claim 1, wherein theplurality of upper supporters are separated from the lower supporter. 3.The semiconductor device of claim 1, wherein the lower supporter isunder the upper supporter group, and a distance between the plurality ofupper supporters is less than a distance between the upper supportergroup and the lower supporter.
 4. The semiconductor device of claim 1,wherein a thickness of the lower supporter is less than a thickness ofeach of the plurality of upper supporters.
 5. The semiconductor deviceof claim 1, wherein at least some of the plurality of upper supportershave facing surfaces having flat profiles.
 6. The semiconductor deviceof claim 1, wherein each of the plurality of upper supporters has anopening.
 7. The semiconductor device of claim 1, wherein the lowersupporter includes an opening.
 8. The semiconductor device of claim 1,wherein at least some of the side surfaces of the plurality of electrodestructures are exposed between the plurality of upper supporters, andthe side surfaces have no bowing effect.
 9. A semiconductor devicecomprising: a plurality of electrode structures on a substrate; a firstsupporter, a second supporter, and a third supporter separated from oneanother between upper ends and lower ends of the plurality of electrodestructures; a dielectric layer on the plurality of electrode structures;and an upper electrode on the dielectric layer, wherein an upper surfaceof the first supporter or a lower surface of the second supporter havecurved profiles, and a lower surface of the first supporter and an uppersurface of the second supporter have relatively flat profiles ascompared with the upper surface of the first supporter or the lowersurface of the second supporter, the first supporter has a firstthickness from the upper surface of the first supporter to the lowersurface of the first supporter, the second supporter has a secondthickness from the upper surface of the second supporter to the lowersurface of the second supporter, and at least one of the first thicknessand the second thickness decreases towards the plurality of electrodestructures.
 10. The semiconductor device of claim 9, wherein the uppersurface of the first supporter or the lower surface of the secondsupporter has a convex profile.
 11. The semiconductor device of claim 9,wherein the first supporter, the second supporter, and the thirdsupporter include a substantially similar material.
 12. Thesemiconductor device of claim 9, wherein the third supporter is underthe first supporter and the second supporter relative to the substrate,and a distance between the first supporter and the second supporter isless than a distance between the second supporter and the thirdsupporter.
 13. The semiconductor device of claim 9, wherein a thicknessof the third supporter is less than a thickness of each of the firstsupporter and the second supporter.
 14. A semiconductor devicecomprising: a substrate; an electrode perpendicular to the substrate; afirst supporter having a top surface and a bottom surface, the bottomsurface of the first supporter being substantially parallel to thesubstrate such that the bottom surface of the first supporter isconnected substantially at right angles to the electrode, the topsurface having a different profile from the bottom surface; and a secondsupporter having a top surface and a bottom surface, the secondsupporter being closer to the substrate than the first supporter, thetop surface of the second supporter being substantially parallel to thesubstrate such that the top surface of the second supporter is connectedsubstantially at right angles to the electrode, the bottom surfacehaving a different profile from the top surface, wherein at least one ofthe first supporter and the second supporter have a thickness thatdecreases towards the electrode.
 15. The semiconductor device of claim14, wherein the first supporter and the second supporter include siliconcarbon nitride.
 16. The semiconductor device of claim 15, wherein apercentage of carbon in the silicon carbon nitride is between 0.1 atom %to 15 atom %.
 17. The semiconductor device of claim 14, wherein theelectrode includes at least one of doped polysilicon, titanium nitride,tungsten, titanium, ruthenium, and tungsten nitride.
 18. Thesemiconductor device of claim 1, wherein the upper surface has a flatprofile, and the lower surface has a curved profile.
 19. Thesemiconductor device of claim 1, wherein the lower surface contacts theside surfaces at an angle greater than a right angle.
 20. Thesemiconductor device of claim 9, wherein the lower surface of the secondsupporter has a curved profile.